Prognostic Value of Baseline Systemic Immune-Inflammation Index in Advanced Intrahepatic Cholangiocarcinoma Treated with First-Line Gemcitabine–Cisplatin Plus PD-L1 Inhibitor: A Single-Center Retrospective Study

Baseline SII is a readily available prognostic biomarker associated with objective response and survival in patients with advanced ICC treated with first-line GC plus PD-L1 inhibitor. Given the retrospective single-center design, the absence of a non-immunotherapy comparator cohort, and internal cut-off derivation, these findings should be interpreted as hypothesis-generating and warrant external validation.